One possible explanation (atleast for some of these apple nostr user cases 😅): They invest in Bitcoin just to make money and not because of its freedom philosophy. The Bitcoin they hold becomes a status symbol, such as their Apple products. They wanna show off their status symbol. They know that many other Bitcoiners are on Nostr. Nostr for them is like an oldtimer-car club, a place to show of their trophies.

And for the linux users preferring non-foss social networks: being a linux user doesn't automatically make you pro freedom 🙈.